Global Volcanism Program | Report on Akutan (United States)

Report on Akutan (United States) — January 1987

Scientific Event Alert Network Bulletin, vol. 12, no. 1 (January 1987)
Managing Editor: Lindsay McClelland.

Akutan (United States) Steam and ash emission

Please cite this report as:

Global Volcanism Program, 1987. Report on Akutan (United States) (McClelland, L., ed.). Scientific Event Alert Network Bulletin, 12:1. Smithsonian Institution. https://doi.org/10.5479/si.GVP.SEAN198701-311320

Akutan

United States

54.134°N, 165.986°W; summit elev. 1303 m

All times are local (unless otherwise noted)

From 5 January to 11 February intermittent steam and ash plumes were reported from a cinder cone (table 1). Minor ashfall occurred at Akutan village on 1 February.

Table 1. Summary of reports of activity at Akutan, 5 January-3 March 1987, collected by J. Reeder. Observers (initials in brackets): Tom Madsen, Aleutian Air; Harold Wilson, Guy Morgan, Theresa Dubber (passenger), Nick Sias, Peninsula Airways; Lee Goch, Don Munson, Janice Reeve Ogle, Reeve Aleutian Airways; David McGlashan, Akutan village; Teddy Jepsen, Trident Sea Foods Corp., Akutan; Jerry Chisum and Ray Wells, Markair; Captain Mets and the 17th Tactical Airlift Squadron; Julie Hathaway and Abi Dickson, Unalaska; Stan Carrick and Ed Collazzi, State of Alaska Hydrologists.

Date	Time	Activity [with observers]
05 Jan 1987	1150	Above-average steaming and sulfuric odors [TM].
05 Jan 1987	1600	Steam plume rose 180 m above the cinder cone; melted snow left black areas on the cone [HW].
31 Jan 1987	1100	Steam and ash plume drifted NW [TM].
31 Jan 1987	1500	Minor steam emission [LG, DM, JO].
02 Feb 1987	1030	Vertical ash plume grew to 900 m; upper N flank covered with fresh ash [TJ].
02 Feb 1987	1445	No ash or steam emissions [LG, JF].
03 Feb 1987	1435	530-m-high steam-and-ash plume; most ash emitted from an upper NW-flank vent on the cinder cone; steam plume on the upper S flank [TM].
03 Feb 1987	1510	180-m-high plume drifting 9 km NE; ash covered the caldera [GM, TD].
07 Feb 1987	1220	Dark-brown ash plume extended 5.5 km NE; plume was gone 1 hour later [JC].
10 Feb 1987	1950	Plume reached 4,900 m altitude (summit altitude is 1,300 m) and drifted 8 km N [CM].
11 Feb 1987	a.m.	Gray ash plume rose continuously; drifted SW; fresh black ash visible on upper N flank [TJ].
11 Feb 1987	1015	Plume reached 300 m above the summit; drifted 65-75 km WSW [TM].
11 Feb 1987	1247	Dark brownish-gray plume rose to 2,100 m altitude, drifted W [JC].

Geological Summary. Akutan contains a 2-km-wide caldera with a large cinder cone in the NE part of the caldera that has been the source of frequent explosive eruptions and occasional lava effusion that covers the caldera floor. An older, largely buried caldera was formed during the late Pleistocene or early Holocene. Two volcanic centers are located on the NW flank. Lava Peak is of Pleistocene age, and a cinder cone lower on the flank produced a lava flow in 1852 that extended the shoreline of the island and forms Lava Point. The 60-365 m deep younger caldera was formed during a major explosive eruption about 1,600 years ago and contains at least three lakes. A lava flow in 1978 traveled through a narrow breach in the north caldera rim almost to the coast. Fumaroles occur at the base of the caldera cinder cone, and hot springs are located NE of the caldera at the head of Hot Springs Bay valley and along the shores of Hot Springs Bay.

Information Contacts: J. Reeder, ADGGS.